I keep losing the cloud icon from the library menu.

I keep losing the cloud icon, and the photos i downloaded from the cloud, from the iphoto library menu. It was there and now its not. Second time. FIrst time i deleted iphoto and re-downloaded from the app store. iCloud works with my other machines and was working fine on this one. It is enabled in iphoto preferences, and i checked icloud preferences in the sys pref pane and all seems well. Any suggestions?